Humidifier

ABSTRACT

A humidifier which in its preferred form has a water receptacle which is vertically expandable and collapsible and provided with a float at its upper end connected to the side wall of the receptacle. The humidifying means comprises a water absorbing, air permeable member and/or a water slinger driven by an air impeller. A shroud forms an air passageway having inlet and outlet openings. At least a portion of the shroud forms the inlet opening and the moisturizing means are supported by the float for vertical movement in accordance with changes in the water level.

United States Patent Blaszkowski [4 Feb. 4, 1975 HUMIDIFIER 1,952,269 3/1934 Lundquist 261/120 [76] Inventor: Henry Blaszkowski, PO. Box 11 1/132? l lii v fi i i i I i H southfield, Mich. 48075 [22] Filed: June 14, 1973 Primary Examiner-Frank W. Lutter Assistant Examiner-William Cuchlinski, Jr. [21] Appl' 370066 Attorney, Agent, or Firm-Barnes, Kisselle Raisch &

Related US. Application Data Choate [63] Continuation of Ser. No. 89,623, Nov. 16, 1970,

abandoned. [57] ABSTRACT A humidifier which in its preferred form has a water [52] [1.8. CL, 261/24, 261/72 R, 261/9], receptacle which is vertically expandable and collaps 261/12 C ible and provided with a float at its upper end con- [51] I111. Cl. B01f3/04 nected to the Side wall of the receptacle The i [58] Field of Search 261/24, 72, 91, 120 fying means comprises a water absorbing, air permew ble member and/or a water slinger driven by an air im- [56] References C'ted peller. A shroud forms an air passageway having inlet UNITE STAT S TE S and outlet openings. At least a portion of the shroud 182,345 9/1876 Bickford 261/120 forms the inlet opening and the moisturizing means 362,197 5/1887 Bennett 261/120 are supported by the float for vertical movement in 6 9, 7/l899 Ma ette 261/120 accordance with changes in the water level. 951,590 3/1910 Brown 261/120 1,064,102 6/1913 Keiver et a1. 261/120 26 Claims, 10 Drawmg Figures PATENTED EB SHEET 2 OF 4 rdmw, M s M ATTORNEYS v E FEB 4|U75 PM NIED I SHEET m a 3 864 437 INVEN'I'OR. H E NRY BLASZ KOWSKI ATTORNEYS PATENTEDFEB-MBYS SHEET L 0F 4 FIG. 3

INVENTOR. HENRY BLASZKOWSKI AATTOEHUE\QS I-IUMIDIFIER This is a continuation of application Ser. No. 089,623, filed Nov. l6, I970, now abandoned.

This invention relates to an air humidifier and, more particularly, to a humidifier of the type having a receptacle periodically filled with water.

One of the problems associated with many conventional room humidifiers is that frequently the efficiency varies with the water level in the water receptacle. Thus, with such humidifiers maximum efficiency is obtained only when the water level lies within a predetermined range. For this reason such humidifiers frequently have a water receptacle of shallow depth and large horizontal surface area.

The present invention has for its object the provision of a humidifier of compact size and of relatively large water capacity which is designed to operate efficiently until the receptacle is practically empty.

More specifically, it is an object of this invention to provide an air humidifier wherein the means for humidifying the air floats in the water receptacle so that it rises and falls with the water level in the container and thus maintains the same relative position with respect to the water level in the receptacle.

A further object as the invention resides in the provision of a humidifier having an air flow passageway provided with inlet and outlet openings, one of which is designed to rise and fall with the water level so that in conjunction with the floating humidifying means the efficiency remains substantially constant regardless of the water level.

Another object of the invention is to provide a water receptacle for a humidifier or the like which is selferecting as it is filled with water and self-collapsing when the water level recedes. This feature not only results in a compact size for storage but, when used without a surrounding cabinet, is self-indicating when refilling is required.

A still further object of the invention resides in the provision of an air humidifier which can be constructed inexpensively and is capable of imparting a relatively high humidity to a large volume of air.

Further objects and features of the invention will become apparent from the accompanying description and drawings, in which:

FIG. 1 is a side elevational view, partly in section, of an air humidifier according to the present invention, the water receptacle being shown in the filled or nearly filled condition.

FIG. 2 is a view similar to FIG. 1 and showing the water receptacle nearly empty.

FIGS. 3, 4 and 5 are side elevational views, partly in section, of different embodiments of humidifiers according to the present invention.

self-erecting as it is filled with water and self-collapsing as the water level recedes. Receptacle 10 generally comprises a side wall I2 formed-of a flexible material (such as plastic) of generally bellows configuration. Around the inner periphery of side wall 12 at the upper end thereof there is secured to the side wall a float 14. Float I4 can be in the form of a hollow plastic ring or can be formed as a ring from a solid bouyant material such as styrofoam. In any event, float I4 is arranged within the upper end of receptacle I0 so that it is bouyantly supported by the water in the receptacle whereby as the receptacle is filled with water the float vertically expands side wall I2 (FIG. I) and as the water level in the receptacle recedes the float 14 causes the side wall 12 to vertically collapse (FIG. 2). Collapse of side wall 12 is assisted by the weight of the fan assembly on float I4. In the embodiments illustrated in FIGS. I and 2 the bellows construction of side wall 12 illustrates by way of example one form of receptacle construction that may be employed. However, any suitable constructionv of the side wall which enables it to become self-erecting and self-collapsing may be utilized. The bellows construction shown in FIGS. 1 and 2 may include an internal vertically telescoping strut 13 for imparting lateral stability to the receptacle. Strut I3 is secured to the bottom wall of the receptacle at its lower end and to a brace 15 on float 14 at its upper end.

A shroud 16 is supported upon float I4. Shroud 16 includes a vertically extending cylindrical side wall 18 having a horizontally extending flange 20 at its lower end. A plurality of circumferentially spaced brackets 22 support shroud 16 on float I4 with the circular flange 20 spaced slightly above the top of the float 14 so as to provide annular air inlet openings 24. Within shroud 16 there is mounted a fan assembly which includes an electric motor 26 which drives a multi-blade impeller 28.

An annular wall 30 is secured to the underside of flange 20 so that it extends downwardly below the level of the water in receptacle 10. The water level is designated 32. In the embodiments shown in FIGS. I and 2 wall 30 comprises the means for moisturizing the air. This wall is formed of a water absorbing, air permeable material such as a polyurethane foam or the like. It may also serve as a dust filter or may be surrounded with a material which serves as a dust filter. In any event, wall 30 has its lower end immersed in water so that by capillary action the wall becomes water saturated. Fan blades 28 are rotated so as to draw air into the shroud through inlets 24 and exhaust the air through theopen upper end 34 of cylindrical wall I8. As the air is drawn in through inlets 24 it flows through the air permeable wall 30, picks up moisture and is then directed back into the room through outlet 34. Since wall 30 and the fan assembly are supported on float 14, as the water level recedes the whole assembly descends and the lower end of wall 30 remains at all times immersed in the water as indicated in FIG. 2. Thus, regardless of the water level in the receptacle, the air moisturizing means and the air inlets are fixed relative to the water level and the efficiency of the humidifying action remains substantially constant. With the arrangement as illustrated receptacle 12 can be dimensioned so as to be relatively'deep and, thus, have a relatively large capacity without requiring refilling for a substantially long period of time.

The arrangement shown in FIG. 3 is generally the same as that shown in FIGS. 1 and 2 except that additional means are provided for soaking annular wall 30 with water. These means are in the form of a water slinger 36 mounted on the output shaft 38 of motor 26. The water slinger comprises a plurality of radially extending arms 40 which are inclined downwardly toward the surface of the water. At their outer ends arms 40 are provided with vanes or blades 42 which are partially immersed in the water and disposed such that when motor 26 is operated they spray water radially outwardly against annular wall 30 and thus additionally wet wall 30 as the air is flowing therethrough. In FIG. 3 lateral stability is provided by three or more upright rods 41 positioned around the outer periphery of the receptacle and mounted on a base 43.

In the humidifier illustrated in FIG. 4 the construction is somewhat similar to that shown in FIG. 3. However, the water slinger 44 has vanes or blades 46 thereon which are designed to spray water droplets upwardly into the fan blades 28 when fan motor 26 is operated. This causes the air flowing upwardly through the shroud to become saturated with moisture. With the arrangement shown in FIG. 4 it is desirable to form wall 30 of a water absorbing material, but this is not essential. In the form shown in FIG. 4 wall 30 need only be an air permeable wall to enable the flow of air into the shroud through inlets 24 into contact with the water droplets or spray produced by blades 46. Alternatively wall 30 in FIG. ,4 can be formed as an imperforate member with its lower edge spaced above the water level 32 so that the air merely flows inwardly below the edge of wall 30 above the water level in the receptacle. In any event, the air flowing upwardly into the shroud comes into intimate contact with the water spray or droplets produced by vanes 46 and is propelled by the wet blades 28 to substantially increase the humidity thereof.

The water slingers 36 and 44 illustrated in FIGS. 3 and 4 are merely exemplory of various types of moisturizers that may be employed. A conventional cone type moisturizer may be employed but the latter requires high speed operation and, thus, produces considerable noise. Slingers 36 and 44 produce an adequate spray at only moderate speeds.

in the arrangement illustrated in FIG. water receptacle 48 has a side wall 50 formed of a flexible limp material, such as plastic. The side wall is reinforced by a plurality of vertically spaced rings 52. A float 54 is connected with the upper end of side wall 50 around the inner periphery thereof. In this arrangement receptacle 48 is disposed within an outer enclosure or cabinet having a side wall 56. Wall 56 is air permeable throughout its vertical extent. A plurality of circumferentially spaced upright channel guides 58 around the inner periphery of wall 56 is provided for imparting lateral stability to the side wall 50 of receptacle 48. Guide pins 60 around the outer periphery of float 54 are adapted to engage in the guide channels 58 so as to retain float 54 and side wall 50 generally concentric with the outer side wall 56.

In FIG. 5 the moisturizing means comprise an annular wall 62 secured to float 54 around its outer periphery. Wall 62 is formed of a water absorbing. air permeable material. The fan motor 64 is mounted within a generally conically shaped shroud 66 with the fan blades 68 disposed below the shroud. Shroud 66 has its 4 outer peripheral edge portion supported on and radially inwardly of the upper edge of outer wall 56 by a plurality of upstanding brackets 68. A conical flange 70 projecting radially inwardly and downwardly from the upper end of outer wall 56 has an annular depending wall 72 which is telescopically engaged with an annular wall 74 connected with the upper end of wall 62. Thus, with this arrangement as the water level 76 in receptacle 48 rises and falls, although the fan assembly remains stationary, the air moisturizing member and the air inlet opening (namely, wall 62) rises and falls with the water level while maintaining the side walls 72,74 in telescoping sliding relation.

In the arrangement shown in FIG. 5 outer wall 56 is formed as an air permeable filter to trap dust and the like and to provide an inlet for air to the humidifier. The air outlet is formed by the openings 78 at the upper end of the unit between flange 70 and shroud 66. Outer wall 56 need not be formed as an air filter as long as air is capable of flowing through it and as long as it is capable of supporting the fan and shroud structure. Thus. outer wall 56 may merely be formed as .a perforated rigid panel of steel, plastic, or the like.

The arrangement shown in FIG. 7 includes a water receptacle 80 formed of a rigid self-supporting material having a plurality of openings 82 around its periphery at the upper end portion thereof. A conically shaped shroud 84 is secured to the upper end of wall within the receptacle. Shroud 84 supports fan motor 86. A water absorbing, air permeable wall 88 is secured to the inner periphery of a float 90 within the container. The upper end of wall 88 is connected with the lower end of shroud 84 by an imperforate expanding bellows 92. With this arrangement when fan motor 86 is operated room air is drawn into receptacle 80 through openings 82 and into moisturizing chamber through the inlet provided by the water soaked wall 88. The air is then directed upwardly through the annular outlet 94 by the fan. As the level of the water in the receptacle recedes float 90 and wall 88 descend with the water level, thus causing bellows 92 to expand while constraining all the air to flow through the moisturizing wall 88.

In FIG. 8 the water receptacle is substantially the same as shown in FIG. 1 including the side wall 12 and the float 14. In this arrangement a vertically extending cylindrical wall 96 is mounted on the float. The fan and moisturizing assembly 98 comprises a vertically extending inner cylindrical wall 100 on which fan motor 102 is rigidly supported by means of a radially extending brace 104. Wall 100 is pivotally supported for rocking movement on wall 96 about the axis 106. [n this arrangement the air moisturizing means is in the form of a shallow panshaped member 108 having a side wall 110 and a bottom wall 112. Member 108 is formed of a water absorbing, air permeable material and is secured to the lower end of wall 100. Member 108 is disposed such that when wall 100 is in its normally upright, vertically extending position the lower end of member 108 and more specifically the bottom wall 112 thereof is preferably submerged in the water. Motor 102 operates a crank disc 114 which is connected by a link 116 to an upright strut 118 fixedly mounted on wall 96. Thus, when the fan motor is operated air is drawn downwardly between walls 96 and 100 and into the moisture chamber or duct through member 108 and then is discharged upwardly in the space within wall 100 around motor 102. At the same time the whole assembly 98 is rocked about axis 106 so that diametrically opposite sides of member 108 are alternately deeply submerged in the water and then elevated above the water so as to insure a free flow of air through the unit while obtaining a maximum moisturizing effect.

in the humidifier arrangement shown in FIG. 9 two receptacles 120,122 are employed. These receptacles are interconnected at their lower ends by a communicating duct 124. A humidifying and air propelling arrangement. generally designated 126, is associated with receptacle 122. The humidifying and air propelling arrangement 126 may be constructed in accordance with any of the previous embodiments illustrated so that the moisturizing means and the inlet to the moisturizing chamber floats on and rises and falls with the level of the water in receptacle 122. Receptacle 122 can either be a rigid one such as shown at 80 in FIG. 7 or a collapsible one such as shown in the other embodiments described above. Likewise receptacle 120 can be either rigid or self-collapsing. ln any event, filling of receptacle 120 raises the water level in receptacle 122 to the same height so that the humidifier can operate without refilling until both receptacles are practically empty.

In FIG. there is illustrated another form of receptacle which is of relatively inexpensive construction. The receptacle comprises a bottom wall 128 and a side wall 130 formed of a flexible material such as plastic. The upper end of wall 130 is wrapped around a float 132 in a direction upwardly around the inside of the float and then downwardly around the outside of the float. The free edge of wall 130 is provided with a draw string 134 for effectively securing the float to the upper end of the wall. Float 132 has an inner diameter substantially smaller than the diameter of wall 130 so that when the receptacle is filled with water float 132 is, by necessity, bouyantly supported by the water. Thus, the receptacle becomes self-erecting when it is filled with water and self-collapsing when the water level recedes. The humidifying and air propelling mechanism is adapted to be supported on flat 132 by an annular bracket 135 which rests upon or is secured to the float. It will be appreciated that the receptacle shown in FIG. 10 as well as the collapsible receptacles shown in the other embodiments illustrated and described have utility in arrangements other than the humidifier shown and described herein.

When the humidifier employs a collapsible receptacle of the type shown it can be reduced to a very compact size when not in use even though it has a relatively large capacity. As pointed out above, the collapsible feature also provides a self-evident indication when the receptacle needs refilling.

'Of even greater importance is the fact that the moisturizing means and the means providing the inlet to the moisturizing chamber or duct (or the outlet, if the fan rotation is reversed) rise and fall with the water level in the receptacle throughout substantially the entire vertical extent of the receptacle. This feature accounts for a substantially constant high efficiency in a large capacity humidifier which does not require refilling for relatively long periods of time.

It will also be appreciated that the device described can also be used as an air circulating fan when the container is not filled with water. If such use is contemplated the fan motor would be of the two-speed type, the low speed being employed when used as a humidifier and the high speed being used for air circulation purposes. To improve the efficiency of the device as an air circulating fan the moisturizing wall would be re moved unless an air filtering action is also desired. When the device is used for air circulating purposes bellows 92 woud be disconnected from the lower end of shroud 84 in the embodiment illustrated in H6. 7 and the inner annular wall 74 would be disconnected from the outer wall 72 in the embodiment illustrated in FIG. 5.

l claim:

1. A humidifier comprising a receptacle for water,

float means adapted to be bouyantly supported by water in the receptacle. said receptacle having a vertically expandable and contractible side wall, said float means being connected to said side wall adjacent the upper end thereof, air moisturizing means supported by the float means to rise and fall with the water level in the receptacle, said moisturizing means having an outlet opening exteriorly of the receptacle for discharging moisture into the surrounding atmosphere.

2. A humidifier comprising a receptacle for water. a float means adapted to be bouyantly supported by the water in the receptacle, means forming an air duct, moisturing means in the air duct contacting the water, said moisturizing means being supported by the float means to rise and fall with the water level in the receptacle, means forming an inlet opening and an outlet opening in said duct, the means forming one of said openings being carried by the float such that said one opening rises and falls with the water level in the receptacle and means for propelling air into said duct,

through said inlet opening, through said duct, and

thereafter out through said outlet opening, said receptacle having a vertically expandable and contractible side wall, the upper edge portion of said side wall being connected with said float means.

3. A humidifier comprising a receptacle for water, a float adapted to be bouyantly supported by the water in the receptacle, means forming an air duct, moisturizing means in the air duct contacting the water, said moisturizing means being supported by the float to rise and fall with the water level in the receptacle, means forming an inlet opening and an outlet opening in said duct, the means forming one of said openings being carried by the float such that said one opening rises and falls with the water level in the receptacle and means for propelling air into said duct, through said inlet opening, through said duct, and thereafter out through said outlet opening, said air propelling means comprising a motor driven impeller in said duct carried by said float.

4. A humidifier comprising a receptacle for water, a float adapted to be bouyantly supported by the water in the receptacle, means forming an air duct, moisturizing means in the air duct contacting the water, said moisturizing means being supported by the float to rise and fall with the water level in the receptacle, means forming an inlet opening and an outlet opening in said duct, the means forming one of said openings being carried by the float such that said one opening rises and falls with the water level in the receptacle and means for propelling air into said duct, through said inlet opening, through said duct, and thereafter out through said outlet opening, said receptacle having a vertically expandable and contractible side wall, the upper edge portion of said side wall being connected with said float.

5. A humidifier comprising a receptacle for water, a float adapted to be bouyantly supported by the water in the receptacle, means forming an air duct, moisturizing means in the air duct contacting the water, said moisturizing means being supported by the float to rise and fall with the water level in the receptacle, means forming an inlet opening and an outlet opening in said duct, the means forming one of said openings being carried by the float such that said one opening rises and falls with the water level in the receptacle and means for propelling air into said duct, through said inlet opening, through said duct, and thereafter out through said outlet opening, said air propelling means comprising a motor driven impeller in said duct and said moisturizing means comprising means forming a water slinger driven by said motor for producing a dispersion of water droplets in said duct.

6. A humidifier as called for in claim wherein said moisturizing means also includes an air permeable member wetted by the water in the receptacle and through which at least a portion of the air propelled in the duct is constrained to flow.

7. A humidifier as called for in claim 6 wherein said water slinger is adapted to direct water droplets against the air permeable member.

8. A humidifier as calledfor in claim 6 wherein the water slinger is adapted to wet the impeller blades.

9. A humidifier comprising a water receptacle having a side wall, a bottom wall and an open upper end, a motor driven air impeller at the open upper end of the receptacle, a generally vertically extending annular member circumscribing said impeller and extending downwardly therefrom, at least the lower section of said annular member being formed of a water absorbent material which is adapted to retain water and which is readily air permeable so that air can flow laterally through said lower section, means for maintaining said lower section saturated with water and a float supporting said lower section of said annular member on the water in the receptacle such that the lower portion thereof is partially submerged and the upper portion of the lower section extends upwardly above the level of the water in the receptacle around its entire periphery such that when the impeller is rotated air is directed laterally through the portion of the water saturated section extending above the water level to thereby moisturize said air.

10. A humidifier as called for in claim 9 wherein said lower section of the annular member is disposed slightly laterally inwardly of the side wall of the receptacle to define an annular air passageway around the outer periphery of said lower section.

11. A humidifier as called for in claim 9 wherein the upper portion of said annular member defines an air duct extending upwardly above said impeller.

12. A humidifier as called for in claim 9 wherein said impeller is supported by said float.

13. A humidifier as called for in claim 9 wherein said annular member circumscribes an area at the water level which has a cross dimension forming a major portion of the cross dimension of the upper open end of the receptacle.

l4. A humidifier as called for in claim 9 wherein said impeller is adapted to rotate about a vertical axis and has blades which extend radially outwardly to closely adjacent the inner periphery of said annular member for producing a relatively large volume of air flow with a minimum of pressure drop across said lower section of the annular member.

15. A humidifier as called for in claim 9 wherein said annular member is supported by said float.

16. A humidifier as called for in claim 15 wherein said air impeller is supported by said annular member.

17. A humidifier as called for in claim 9 wherein said means for maintaining the lower section of said annular member saturated with water includes means within said annular member for directing water droplets to the portion of the lower section of the annular member above the water level.

18. A humidifier as called for in claim 9 including means for cyclically varying the extent to which the lower section of said annular member is immersed in the water. I

19. A humidifier a called for in claim 9 wherein said motor driven impeller is supported in a vertically fixed position independently of said float, said annular member having its upper section fixed relative to the impeller and an extensible portion interconnecting said lower and upper sections.

20. A humidifier as called for in claim 9 wherein the float is disposed radially inwardly of the receptacle side wall.

21. A humidifier as called for in claim 20 wherein said side wall comprises a bellows arrangement.

22. A humidifieras called for in claim 21 including means providing lateral support to the receptacle.

23. A humidifier as called for in claim 22 wherein said last-mentioned means comprises a supporting wall extending exteriorly around the side wall of the receptacle.

24. A humidifier as called for in claim 23 wherein said supporting wall is air permeable.

25. A humidifier as called for in claim 23 wherein said supporting wall comprises an air permeable filter.

26. A humidifier as called for in claim 23 including means forming vertically extending guideways around the inside of said supporting wall and means on said float engaging said guideways.

UNITED STATES PATEIiT OFFICE CERTIFICATE OF CORRECTION Patent No. 6 Dated February 4, 1975 Invencor(s) BLASZKOWSKI, Henry It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

Column 7, Line 26 Cancel "6" and insert 5 Colufnn 8, Line 29 Cancel "a" and insert as gned an: sealed this 8th day of April 1975.

(FT-"L? 1 test:

C. MARSHALL DANE 7' a '12 w I 13TH o -izkoqh Commissioner of Patents attesting Orf'icer and Trademarks 

1. A humidifier comprising a receptacle for water, float means adapted to be bouyantly supported by water in the receptacle, said receptacle having a vertically expandable and contractible side wall, said float means being connected to said side wall adjacent the upper end thereof, air moisturizing means supported by the float means to rise and fall with the water level in the receptacle, said moisturizing means having an outlet opening exteriorly of the receptacle for discharging moisture into the surrounding atmosphere.
 2. A humidifier comprising a receptacle for water, a float means adapted to be bouyantly supported by the water in the receptacle, means forming an air duct, moisturing means in the air duct contacting the water, said moisturizing means being supported by the float means to rise and fall with the water level in the Receptacle, means forming an inlet opening and an outlet opening in said duct, the means forming one of said openings being carried by the float such that said one opening rises and falls with the water level in the receptacle and means for propelling air into said duct, through said inlet opening, through said duct, and thereafter out through said outlet opening, said receptacle having a vertically expandable and contractible side wall, the upper edge portion of said side wall being connected with said float means.
 3. A humidifier comprising a receptacle for water, a float adapted to be bouyantly supported by the water in the receptacle, means forming an air duct, moisturizing means in the air duct contacting the water, said moisturizing means being supported by the float to rise and fall with the water level in the receptacle, means forming an inlet opening and an outlet opening in said duct, the means forming one of said openings being carried by the float such that said one opening rises and falls with the water level in the receptacle and means for propelling air into said duct, through said inlet opening, through said duct, and thereafter out through said outlet opening, said air propelling means comprising a motor driven impeller in said duct carried by said float.
 4. A humidifier comprising a receptacle for water, a float adapted to be bouyantly supported by the water in the receptacle, means forming an air duct, moisturizing means in the air duct contacting the water, said moisturizing means being supported by the float to rise and fall with the water level in the receptacle, means forming an inlet opening and an outlet opening in said duct, the means forming one of said openings being carried by the float such that said one opening rises and falls with the water level in the receptacle and means for propelling air into said duct, through said inlet opening, through said duct, and thereafter out through said outlet opening, said receptacle having a vertically expandable and contractible side wall, the upper edge portion of said side wall being connected with said float.
 5. A humidifier comprising a receptacle for water, a float adapted to be bouyantly supported by the water in the receptacle, means forming an air duct, moisturizing means in the air duct contacting the water, said moisturizing means being supported by the float to rise and fall with the water level in the receptacle, means forming an inlet opening and an outlet opening in said duct, the means forming one of said openings being carried by the float such that said one opening rises and falls with the water level in the receptacle and means for propelling air into said duct, through said inlet opening, through said duct, and thereafter out through said outlet opening, said air propelling means comprising a motor driven impeller in said duct and said moisturizing means comprising means forming a water slinger driven by said motor for producing a dispersion of water droplets in said duct.
 6. A humidifier as called for in claim 5 wherein said moisturizing means also includes an air permeable member wetted by the water in the receptacle and through which at least a portion of the air propelled in the duct is constrained to flow.
 7. A humidifier as called for in claim 6 wherein said water slinger is adapted to direct water droplets against the air permeable member.
 8. A humidifier as called for in claim 6 wherein the water slinger is adapted to wet the impeller blades.
 9. A humidifier comprising a water receptacle having a side wall, a bottom wall and an open upper end, a motor driven air impeller at the open upper end of the receptacle, a generally vertically extending annular member circumscribing said impeller and extending downwardly therefrom, at least the lower section of said annular member being formed of a water absorbent material which is adapted to retain water and which is readily air permeable so that air can flow laterally through said lower section, meAns for maintaining said lower section saturated with water and a float supporting said lower section of said annular member on the water in the receptacle such that the lower portion thereof is partially submerged and the upper portion of the lower section extends upwardly above the level of the water in the receptacle around its entire periphery such that when the impeller is rotated air is directed laterally through the portion of the water saturated section extending above the water level to thereby moisturize said air.
 10. A humidifier as called for in claim 9 wherein said lower section of the annular member is disposed slightly laterally inwardly of the side wall of the receptacle to define an annular air passageway around the outer periphery of said lower section.
 11. A humidifier as called for in claim 9 wherein the upper portion of said annular member defines an air duct extending upwardly above said impeller.
 12. A humidifier as called for in claim 9 wherein said impeller is supported by said float.
 13. A humidifier as called for in claim 9 wherein said annular member circumscribes an area at the water level which has a cross dimension forming a major portion of the cross dimension of the upper open end of the receptacle.
 14. A humidifier as called for in claim 9 wherein said impeller is adapted to rotate about a vertical axis and has blades which extend radially outwardly to closely adjacent the inner periphery of said annular member for producing a relatively large volume of air flow with a minimum of pressure drop across said lower section of the annular member.
 15. A humidifier as called for in claim 9 wherein said annular member is supported by said float.
 16. A humidifier as called for in claim 15 wherein said air impeller is supported by said annular member.
 17. A humidifier as called for in claim 9 wherein said means for maintaining the lower section of said annular member saturated with water includes means within said annular member for directing water droplets to the portion of the lower section of the annular member above the water level.
 18. A humidifier as called for in claim 9 including means for cyclically varying the extent to which the lower section of said annular member is immersed in the water.
 19. A humidifier a called for in claim 9 wherein said motor driven impeller is supported in a vertically fixed position independently of said float, said annular member having its upper section fixed relative to the impeller and an extensible portion interconnecting said lower and upper sections.
 20. A humidifier as called for in claim 9 wherein the float is disposed radially inwardly of the receptacle side wall.
 21. A humidifier as called for in claim 20 wherein said side wall comprises a bellows arrangement.
 22. A humidifier as called for in claim 21 including means providing lateral support to the receptacle.
 23. A humidifier as called for in claim 22 wherein said last-mentioned means comprises a supporting wall extending exteriorly around the side wall of the receptacle.
 24. A humidifier as called for in claim 23 wherein said supporting wall is air permeable.
 25. A humidifier as called for in claim 23 wherein said supporting wall comprises an air permeable filter.
 26. A humidifier as called for in claim 23 including means forming vertically extending guideways around the inside of said supporting wall and means on said float engaging said guideways. 